Thread controlling mechanism



Jan. 27, 1942. R. ABRAMS THREAD CONTROLLING MECHANISM Filed July 13,1958 2 Sheets-Sheet 1 Mam/70R: IPIMMF' ABM/v.2 F

Jan. 27, 1942. R. ABRAMS 2,270,859

THREAD CONTROLLING MECHANISM Filed July 15, 1958 2 Sheets-Sheet 2VVE/YZWE: JPUJMZF ABM/1.1: By mzz A'Trjy Patented Jan. 27, 1942 UNITEDSTATES- PATENT OFFICE 2,270,859 THREAD CONTROLLING MECHANISM RudolfAbrams, Bechtelsville, Pa.

Application July 13, 1938, Serial No. 218,991

7 Claims.

The present invention refers to yarn clamping and let-01f devices suchas are used in knitting machines or other textile machinery. Theinvention is especially adapted for use in knitting machines for takingup fine yarns which are fed intermittently and for clamping them exceptat such times as they are fed to the knitting instrumentalities of themachine.

In the figures of drawings:

Fig. 1 is an elevation showing the invention as applied to wrappingmechanism on a typical knitting machine;

Fig. 2 is a section taken through a part of Fig. 1 and showing onetake-up and let-off device to an enlarged scale;

Fig. 3 is a section showing a fragment of the device and illustratingone take-up and let-off assembly as seen from above;

Fig. 4 is a section showing in detail the manner in which a yarn is tobe clamped or held by the device;

Fig. 5 is a detail showing the manner in which the yarn is threaded. Thecase presents certain improvements over the mechanism shown and patentedin Patent 2,091,407 to Robert H. Lawson. In the feeding of certainyarns, especially yarns for wrap striping, some difl'iculties have beenexperienced with the let-off mechanism of said Lawson patent in thatthere would not be a sufficient clamping action especially after thedevice had been used for a considerable period of time. With wiry yarnsand stiff, rough yarns such as spun artificial filaments, there has beena tendency to groove the clamping surfaces so that after a period oftime the yarn would run through the groove or grooves and would not beproperly held. Further, in certain instances, more clamping action isdesired than is possible in said mechanism of the Lawson patent althoughthat mechanism serves very well for a great many types of yarns and/ orfilaments.

Now referring to the figures of drawings wherein mechanism has beenshown as applied to a wrapping mechanism for hosiery machines, I willdescribe the specific details and function of one preferred embodimentof the invention. This particular embodiment applies to wrapp ngmechanism such as used in Banner machines and illustrated in Lawson etal. Patent 1,702,608. While the mechanism is particularly adapted foruse in such wrapping devices, it may be used in wrapping mechanisms ofother types, and further, is well adapted for use in any knittingmaments as a spindle I and a bracket 2 supported on a post 3 whichextends upwardly from the so-called circular base of the machine. Withchines or other textile machines wherein yarns this type of wrappingmechanism rotation of the wrapping devices which cooperate with theneedles as well as the wrap yarn supplies is contemplated. However, theinvention is equally applicable to stationary cylinder machines whereinthese elements would not be rotated but would be caused to function byother elements rotating with respect thereto. Here the spindle I isrotated by gearing (not shown) or in any other suitable way. The spindlealso carries a sleeve 4, a plate 5 upon which are mounted a plurality ofwrap yarn supplies 6 carried on suitable pins or holders 1. The numberof wrap yarn supplies will vary in accordance with the type of machineand other considerations. On a second plate 8 which is fixed at theupper end of sleeve 4, as illustrated in greater detail in Fig. 2, areattached a plurality of let-off devices, one for each of the yarnsupplies. At the topmost portion of spindle l a second sleeve 9 is fixedby a hub I0 which engages over a flange l l on the sleeve and clamps thesame downwardly against plate 8. This hub I9 is slotted radially as at I2 and also circumferentially at I3. A wire 14 fits within thecircumferential slot or groove l3 and serves as a pivot for a pluralityof take-up arms is which serve to take up the slack in their respectivewrap yarns and for another purpose to be described in greater detail asthis disclosure progresses. The groove or slot I3 is undercut at thelower outer edge so that the wire II will spring outwardly and be lockedin place once the assembly has been completed. Each of the takeup armsl5 has a spring l6 attached as illustrated, this spring also being heldby a hook ll adjustably retained as by a set screw I 8 within a flangedcollar l 9 at the upper end of the sleeve 9. These hooks I! may beadjusted to increase or decrease the tension in the springs 16 andthereby to induce different take-up actions in accordance with theparticular yarn size, material, etc.

Adjacent the outer or free end of each take-up arm I5, I provide aneyelet 20 passing through the plate 8 and through which the yarn orfilament may be passed as it is carried downwardly to the knittingpoint. Similar eyelets will be provided in the plate 5. A plurality ofarcuate wires 2| are to be fixed in plate 8 just outside the ring oreyelet. 20 andthe'yarn or filament will be passed beneath this wire 2|,upwardly through an eyelet 22 in the end-of take-up arm It, thendownwardly through the eyelet 20.

Substantially in radial alignmentwith each of these take-up arms I5, Iprovide a yarn clamp and let-off device comprising certain new anduseful features. A post 23 which has been constructed of a piece ofsquare stock turned down for a part of its length serves to clamp a U-shaped thread guiding element 24 in position as said post is maintainedin position by the nut 25. The upper square section of said post isslotted and an arm or lever 26 having an outer curved portion 21 isfreely pivoted on a pin 28. This arm or lever 26 extends inwardly of themachine to terminate in an off-set or angularly bent part 29 whichengages beneath the lever or arm IS.- A block 30 which serves as amovable clamping element is pivoted on a pin. 3| at the lower end ofsaid curved part 21 of the lever 26. This block 30 is slotted as shownin Figs. 3 and 4 and the lower curved end of said lever 26 engageswithin said slot. The clamping side of block 30 is curved to an arc of aradius less than the radius of the circular part of the post 23. Thisassures that there will be a stronger clamping action as illustrated inFig. 4. The block 30 pivots at the pin 3| so that the pressure of theblock will tend to be equalized as it engages post 23, that is, it willpress against the post with a more or less equal force from top tobottom, and will also accommodate itself to different clamping positionsas it would have to for different size of yarn, or in case of lint ordirt lodging beneath it. The U-shaped element 24 has three holes drilledat either side as indicated at 32. There may be more or fewer of theseopenings although three ha been found to be a suitable number. Thethread or filament as it is drawn up from the supply 6 passes through aneyelet 33, then is threaded through the openings 32 from one side to theother and passes behind the post 23, or between the post 23 and theblock 30. For different types of yarn it ha been found desirable to varythe number of passes of yarn between the clamping elements; for sometypes it may be suitable to pass the yarn from one side to the other,other yarns may require two or three passes in order to realize suitableclamping and let-off action. In the particular illustration the yarn ispassed through twice and is then led under the wire 2|, through eyelet22 and then down through other guiding openings to the wrapping andknitting instrumentalities. I refer to the yarn thus threaded as beingpassed a plurality of times through the clamping means.

A spring 34 attaches through a hole about mid-way of the arm 26 andagain to an extension 35 fixed within the slot at the upper end of post23. Several holes are provided in both the arm and the extension so thatdifferent springs may be adjusted to any desired tension by changingfrom one set of holes to another. When the arm 26 is not being helddownwardly thereby extending spring 34 as in Fig. 2, the said springwill pull the arm upwardly and about pivot 28 swinging the block 30inwardly against the yarns passing between it and post 23. This willcause the yarn to be clamped until such time as arm 23 is moveddownwardly against the tension of spring 34 whereupon the clamping block30 will be moved away from the post and the yarns themselves.

At that time the yarns will be drawn freely eyelets and openings.

through the various eyelets and openings through which they arethreaded.

Summing up the operation briefly, the yarn is threaded through theeyelet 33 and through a suitable number of the openings 32 as described,then under wire 2| through the eyelet 22 at the free end of take-up arml3 and thence to the knitting point. If the take-up arm I5 is in anyposition from that illustrated in Fig. 1, to a position wherein it justengages the offset end 23 of arm 23, the clamp 30 will be held againstthe yarn by spring 34 as aforesaid. As the yarn is taken and is drawndownwardly through eyelet 20, the take-up arm I5 will be pulled downwardly against the tension of spring l6 until it engages the offset end29, any further movement of that arm l5 then swinging the longer arm 23about pivot 23 and extending spring 34. A slight movement of the arm 26will withdraw the block 30 sufficiently to release the clamped yarn. Dueto the compound system of levers, it takes very little tension withinthe yarn to release the clamp 30. As long as the yarn is feedingsteadily, arms I5 and 26 will be held as in Fig. 2 and the yarn will bedrawn freely through the various Just as soon as the yarn i not beingtaken, or as soon as the same becomes slack, the take-up arm l5 willmove upwardly, the clamp 30 will engage and hold the yarn passingthrough the openings 32 and no yarn will then be possible of drawingfrom the supply. There is suflicient movement of the takeup arm l5 afterthe clamp has engaged the yarn as just described, to serve the usualtake-up purpose for keeping slack out of a wrap or other yarn. Thisfunction is well known with respect to wrap stripe knitting machines.

The invention has been described with respect to one specificembodiment, but changes will be apparent to those skilled in the art andthe disclosure contemplates such changes without departing from thescope of the invention as originally conceived. The invention is definedin the appended claims.

I claim:

1. A yarn clamping and let-ofl device of the type described includingfixed and movable clamping elements, guiding mean for guiding a yarnbetween said fixed and movable elements having a plurality of openingsso that said yarn may be passed between the elements a plurality oftimes.

2. A yarn clamping and let-ofl device including a fixed and a movableclamping member, guiding means at either side of said clamping membershaving a plurality of yarn guiding openings, said openings being adaptedto guide a yarn between said members a plurality of times.

3. Yarn clamping and letofi means including a post, part of said postbeing adapted for the clamping of a yarn, a movable member for engagingthe clamping portion of said post and a lever pivotable within said postand also pivotally carrying said movable clamping member,

"and yarn guiding means at either side of said post provided with aplurality of openings whereby a yarn may be passed a plurality of timesbetween said post and the movable clamping member.

4. Yarn clamping and let-oil means including a post having a portionthereof of circular cross section, guiding means for guiding a yam to bepassed one side of said post a plurality of times and adjacent saidcircular part thereof, and a movable clamping member adapted to engagethe yarn at said circular part of the post, the clamping portion of saidmember being formed to an arc of lesser radius than the radius of saidcircular part of the post.

5. Yarn clamping and let-01f means of the type described including apost, part of said post being circular in cross-section and the upperportion therefor being slotted, a lever pivoted within said slot andhaving a curved, depending end, a movable clamping element pivoted atsaid curved end, spring means for drawing said lever in a direction topress said clamping member against the circular section of said post,and guiding means adapted to guide a yarn between said post and clampingmember a plurality of times.

6. Yarn clamping and let-off means including a post having a portionthereof circular in crosssection, guiding means for guiding a yarn topass one side of said post a plurality of times and adjacent saidportion of circular cross-section, a movable clamping member adapted toengage the yarn at that part of the post, said clamping member having aclamping surface so constructed as to engage the circular cross-sectionof the post along two independent spaced lines of contact.

7. Yarn clamping and let-ofi means for machines of the type describedincluding a fixed clamping member, a movable clamping member and guidingmeans for guiding a yarn to pass to and fro a plurality of times betweensaid fixed and movable members, the said movable member being mounted topivot freely and in such -a manner as to be self-aligning in itsclamping action against the fixed member.

RUDOLF ABRAMS.

